Hi,
I was wondering if this plug-in is blocking legit search engine bots, because I have my site indexed at Google and I was notified that Google was getting crawl errors at my site? This is what it read:

WordPress generates virtual robots.txt file by itself, so ot is possible that other plugin added some extra entries to it. Please try to navigate to yoursite.com/robots.txt in your browser. WordPress generates only two lines listed below; if you will see something extra, it is added by other plugin(s).